Family-Based Green Card

[Berbatee]

An unmarried child of over 21 years was filled for by her US citizen mother. So his priority date is current and had submitted the required civil documents at the NVC. If he marries while he is waiting for interview without the intent of making his spouse benefit from it at that time will his case be changed to the third preference (F3) if he provide it at his yet to be fixed interview date.

Please I need your favorable response about this case.
Thanks

[newacct]

Yes. He cannot marry before entering the US with his immigrant visa if he is to immigrate in this category.